This tripod adapter allows to use a 1/4" tripod screw in the older (larger) 3/8" tripod sockets.
The adapter is made of nickel-plated brass, with a slot on the top. You can use a flat-head screwdriver to tighten it in your camera body.
The image shows a bottom plate of a Moskva camera with and without the adapter. The camera is for illustration only and is not included.
Buy several and install them on all your cameras.